One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,7)(4,5)(6,8)(9,10,12,14)(11,15,16,13)(17,18,23,26)(19,27,30,32)(20,28,22,25)(21,31,29,24)(2,5)(3,8)(9,11)(10,13)(12,16)(14,15)(17,19,20,21,23,30,22,29)(18,24,25,32,26,31,28,27)(1,3,4,8)(2,6,5,7)(10,14)(11,16)(17,20,23,22)(18,25,26,28)(19,29,30,21)(24,27,31,32)(2,5)(6,7)(10,14)(11,16)(18,26)(19,30)(21,29)(25,28) involution — undirected(2,5)(6,7)(10,14)(13,15)(17,21,20,30,23,29,22,19)(18,27,25,24,26,32,28,31)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.